Development in the solar cell industry is driven by global environmental concerns and rising raw material prices.
The solar cell module comprises a front plate, a solar cell, a sealing material and a back plate. The back plate is often formed by several layers. For example, a back plate is formed by the following steps. A polyethylene terephthalate (PET) is used as a substrate and a fluoropolymer layer is coated on the PET substrate, and then a sealing material (such as ethylene vinyl acetate copolymer (EVA) is adhered to the fluoropolymer layer. However, poor adhesion exists in-between the ethylene vinyl acetate copolymer (EVA) and the fluoropolymer layer.
U.S. Pat. No. 6,074,719 provides a multilayer composition containing a fluoropolymer. An aliphatic diamine or aliphatic polyamine (molecular weight smaller than 1,000) is coated on a substrate, and then a fluoropolymer and the substrate are hot pressed at high temperature to form the multilayer composition.
However, when the aliphatic diamine or aliphatic polyamine is used as an adhesion promoter layer, an unwanted yellowing phenomenon may occur in the fluoropolymer layer, and the fluoropolymer layer is easily peeled off from the substrate.
Therefore, there is a need to develop a multilayer composition containing a fluoropolymer to prevent the yellowing phenomenon and peeling off problem.